1. Technical Field
The disclosure relates to power supply systems, and particularly to a power off delay circuit.
2. Description of Related Art
Electronic devices usually use capacitors charging to provide necessary power to load circuits, such as, central processing units, when power supplies of the electronic devices are off. Because the power need by the load circuits increases with advancing function and process speed, capacitance of the capacitors need to be increased to provide enough power when the power supplies are off. However, the capacitors with large capacitance may not provide enough power off delay time.